This invention relates to diamonds and more particularly to methods of doping diamonds.
It has been widely known for many years that diamond would be greatly superior to either silicon or GaAs as a material for integrated circuits. Reasons include the greater heat conductivity of diamond, the higher carrier mobilities, the higher operating temperatures, and the intrinsic radiating hardness such a "chip" would possess. The problem has been to find a way to dope diamond with suitable impurities to create n- and p- type semiconductors. The very compact structure of diamond coupled with the very high c--c bond energies prevent diffusion of dopants into the material. Moreover, diamond has an extremely high melting temperature, making the liquid hard to form. Ion implantation has been used to introduce the dopants into the structure. However, considerable lattice damage must be produced to allow the impurity atoms to get in. If too much damage is done, subsequent annealing graphitizes the structure. If too little damage is done, the dopants end up in interstitial rather than substitutional sites after annealing. In spite of the difficulties, efforts to produce diamond integrated circuits exceed one hundred million dollars annually.
It would be desirable to provide a practical method of doping diamonds to produce integrated circuits and other semiconductor devices.